Neutrino Mixing and Leptogenesis in a $L_e-L_\mu-L_\tau$ model

TL;DR

This paper extends the Standard Model with right-handed neutrinos and a flavor symmetry to explain neutrino mixing and baryon asymmetry via leptogenesis, achieving experimental consistency with minimal fine tuning.

Contribution

It introduces a SUSY-based model with a non-standard flavor symmetry that successfully reproduces neutrino mixing angles and baryon asymmetry, with detailed numerical analysis.

Findings

Reproduces experimental neutrino mixing angles.

Achieves baryon asymmetry consistent with observations.

Demonstrates minimal fine tuning of parameters.

Abstract

We present a simple extension of the Standard Model with three right-handed neutrinos in a SUSY framework, with an additional U(1$)_\text{F}$ abelian flavor symmetry with a non standard leptonic charge $L_e-L_\mu-L_\tau$ for lepton doublets and arbitrary right-handed charges. We show that the model is able to reproduce the experimental values of the mixing angles of the PMNS matrix and of the $r=\Delta m_\text{sun}^2/\Delta m_\text{atm}^2$ ratio, with only a moderate fine tuning of the Lagrangian free parameters. The baryon asymmetry of the Universe is generated via thermal leptogenesis through CP-violating decays of the heavy right-handed neutrinos. We present a detailed numerical solution of the relevant Boltzmann equation accounting for the impact of the distribution of the asymmetry in the various lepton flavors.